In some cases, all of these methods fail to locate the affected sinus and the cause can be found only by opening into the sinuses, aspirating with a catheter and making microscopic examination of the aspirated material. The microscope is indispensable for this work. Every suspicious discharge should be stained until pus is found and except in well defined cases, this is the only practical method of positive diagnosis. =Treatment.=—Local treatment of the nasal cavities by retracting the turbinates and irrigation will be successful in many cases, but unless there is a large normal opening the pus will not drain sufficiently and probe treatment is required. In acute cases in which the pain is marked, osteopathic treatment of the cervical region, deep relaxation of the submaxillary structures and the application of heat over the affected part, together with the local nasal treatment should be given, but if this does not relieve the pain within twenty-four hours, the sinus should be opened and thoroughly drained. If efficient drainage is not established early the symptoms will usually increase until the pain is almost unbearable and serious complications may result. In practically every case of acute sinuitis, I believe it is best to make a good, free opening into the affected sinus first and secure complete drainage by catheter aspiration. If this is properly done every case will recover much more quickly and without complications or danger of chronic infection. Non-Suppurative Sinuitis Cases of non-suppurative sinus involvement are not at all uncommon. The so-called “Vacuum sinuitis” which results from a closure of the normal opening, resulting in inflammation without pus formation, is responsible for many of the complicated cases of referred pain, which are so often improperly diagnosed. Chronic headaches and the various symptoms of fifth nerve affections, the neuralgias of the head, are frequently caused by non-suppurative sinus involvement. =Treatment.=—The treatment consists of establishing good drainage and proper ventilation of the affected sinus or sinuses followed by thorough intranasal treatment as explained above. The osteopathic corrective work must not be neglected. Syphilis of the Nose In osteopathic practice syphilis is not a common disease. The occurrence of syphilis of the nose is still more rare but certainly should be recognized. =Diagnosis.=—The local lesions of the nose are of two types, those of acquired syphilis and of congenital syphilis.